Boom-swinging means



July 14, 1925.

E. H. LICHTENB'ERG BOOM SWINGING MEANS Ori'ginal'Filed July 19. 1920 SHvc I I ['01 Z/Yjmmiy i or Patented July 14, 1925.

wl'l'ED STATES PATENT OFFICE.

ERICK H. LICHTENBERG, 0 F MILWAUKEE, WISCONSIN, ASSIGNOB TO KOEHRINGCOMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

BOOM-SWINGING- MEANS.

Original application filed July 19, 1920, Serial No. 397,431, now PatentNo. 1,411,217, dated March 28, 1922. Divided and this application filed'March 24, 1922, Serial No. 546,273. Divided and this application filedAugust 15, 1923. Serial No. 657,534.

To all whom it may concern:

Be it known that I, Enron H. LroH'rEN- BERG, a citizen of the UnitedStates, residing at Milwaukee, in the county of Milwaukee and State ofWisconsin, have invented certain new and useful Improvements in Boom-Swinging Means, of which the following is a specification.

This invention appertains to the art of concrete paving machines of theboom and bucket type. Machines of this class consist primarily of aconcrete mixer having a distributor attached thereto and including aboom adapted to swing horizontally and to be raised and lowered. Theboom carries a bucket which conveys the concrete from the mixer to asuitable point of distribution or deposit.

A worm and worm gear mechanism somewhat as shown in Koehring ReissuePatent 13,617, dated Sept. 16, 1913, and in my Letters Patent No.1,141,470 issued June 1st, 1915, is ordinarily employed for compellingthe horizontal swinging of the boom.

My improvements hereof are designed to overcome the tendency existing inthe constructions similar to those of the patents above mentioned,whereby a locking friction is produced between the engaged worm and wormgear contrivances, owing to the momentum of the swinging movement of theboom under the actuation of the worm cooperating with the worm gear.

I accomplish the above result by the mounting of the worm on itsactuating shaft so that the worm is capable of resilient endwisemovement in its relation to the worm gear, notwithstanding that the wormis keyed or splined to its shaft to rotate therewith. The foregoingarrangement eliminates the disadvantageous locking of said parts, andrenders easy the operation of the boom by the worm and the manual meansfor turning the latter, both in respect to initiating as well asstopping the boom swing.

In the accompanying drawings which show the preferred embodiment of myinvention that I have caused to be put into actual use, Figure 1 is atop plan view of the boom and its operation appliances in relation to amixer, only partially trated, and

Figure 2 is a detail view illustrating primarily the worm andv wormgear, its supillusporting bracket, and the actuating means co-actingwith the worm.

This application is a division of my copending application 546,273 filedMarch 24, 1922, said. application being in turn a di vision of myearlier application 397,431 filed July 19,1920, now Patent No. 1,411,217

at 1 as'mounted u on a bracket 2, by means of the horizontal pivotalaxis 3, seen in dotted lines in Figure 1 as connecting the boom withpivot lugs 4 on the worm ear 5. The

worm gear 5 is connected to t e bracket '2' by a vertical pivot 6 shownin dotted lines in Figure 2. The means for swingin the boom 1 comprisesthe shaft 7, manual y rotatable by a wheel short handle 8 and suitablymounted in bearings 9 on the bracket 2,

Theshaft 7 carries the worm 10 which is splined to the shaft to rotatetherewith and to have longitudinal movement relatively thereto. The worm10 engages the worm gear 5 in the well known manner and intermediate theends ofthe worm 10 and the bearings 9 are provided resilient parts inthe form of springs 11. The springs 11 bear equally against'the worm andtend to maintain the latter in a central position between the bearings9.

In the operation of the mechanism above described it will be'apparentthat the worm 10 may be characterized as having a floating mounting onthe shaft 7. Onturning the shaft 7 to swing the boom 1 horizontally, theinitial action of the worm 10 is to yield by compression of one of thesprin s 11 in the direction opposite that in which t e boom will turn.After a slight compression of said spring the boom will begin to swingand the worm will become centralized between the bearings 9 under theaction of the springs 11. I

the shaft 7, if there is continued movement of the boom 1 under theimpetus of its swing produced by the manual operation of the wheel 8,said worm 10 will yield longitudinally on the shaft 7 and there will beno tendency for the parts and 10 to become locked by the frictionincident to the action of the worm 10 as a stop for limiting theswinging or horizontal movement of the boom. Tl1e foregoing action takesplace when the boom 1 is swung in either direction by the worm 10, allin a manner which will be self-evident.

In pratice I have found the foregoing boom swinging means to beexceedingly eiiicient and to excellently accomplish the results forwhich it is designed.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is

1. In aboom and bucket type concrete dis- I tributor, the combination ofa boom, a bucket to traverse the same, and means for turning-said boomcomprising interacting worm gear and worm devices, and means resilientlysupporting one of said devices.

2. In a concrete distributing machine, the combination of a boomdistributing device, and means for turning the same including a wormgear connected with the boom, a worm engaging said gear, manuallycontrolled means for operating the worm, and resilient meansco-operative with one of the gear and worm parts aforesaid,substantially as and for the purpose described.

3. In a concrete distributing machine, the combination of a boomdistributing device, and means for turning the same including a wormgear connected with the boom, a

.worm engaging said gear, manual means to operate the worm including ashaft support- On stoppage of the turning movement 0 1 ing said worm forrotation therewith, and resilient means acting endwise of the worm toresiliently support the same upon the shaft and in proper relation tothe worm gear.

4. In a boom and bucket concrete dis tributor, a boom, a bucket totraverse the boom, means for swinging the boom horizontally including aworm gear affixed to the boom, a manually operated shaft, a worm splinedon said shaft and resilient means bearing endwise and oppositely uponthe ends of the worm for resiliently supporting the same in engagementwith the worm gear.

5. In a concrete distributing machine, the combination with a boom,means for turning the same including a worm gear connected et and meansfor swinging the boom hori-- zontally on the bracket, comprising a wormgear connected to the boom, a worm mounted on the bracket, a shaftcarrying said worm,

bearings at opposite sides of said worm receiving shaft, springs betweensaid bearings and opposite ends of said worm, and means for turning theshaft, the worm being splined to the shaft to have endwise movementpermitted by the resilient action of the springs, and the normal actionof the springs being to centralize the worm between the said bearings.

In testimony whereof I aflix my signature.

' ERICH H. LIGHTENBERG. 4

